I was expecting a bit more everything. I guess it's just the nature of the beast, but I saw nothing even remotely resembling any preconceived notion I had of "flight" there.

Can anyone provide a "trust me, this is groundbreaking stuff" analysis?posted by ShutterBun at 9:13 PM on May 19, 2011

Sorry about the Silverlight, didn't notice. It just shows a test flight, before the official flight in the AP video link, your not missing much. I picked it for the lead because it shows the entire helicopter, which is hard to see in the AP video, otherwise the AP vid has more death defying drama as it soars just inches above the nap of the earth.posted by stbalbach at 9:14 PM on May 19, 2011

Judy Wexler Human is as strong as a horse!posted by av123 at 9:20 PM on May 19, 2011

So this is therefore the first woman-powered helicopter?posted by phenylphenol at 9:22 PM on May 19, 2011

Jesus. I never want to make, or see anyone making, the face that the test pilot was making. Ever again.posted by danny the boy at 9:23 PM on May 19, 2011

Wow, that actually makes human-powered flight look less practical than if nobody had ever done it. In what was obviously a very well designed and very light craft, a very athletic person just bared managed to take off, using their entire body at what was obviously a sprinting pace. That really does not bode well for it ever being anything other than a curiosity.posted by Mitrovarr at 9:38 PM on May 19, 2011 [1 favorite]

That's definitely in the top ten worst typos I've ever made.posted by Mitrovarr at 9:40 PM on May 19, 2011

It's much easier to tell what's going on in the YouTube video. The silverlight is so low quality (for me, anyway), that it looks like the helicopter is just sliding around a bit.
Plus the youtube video actually plays all the way through without re-buffering.posted by Pruitt-Igoe at 10:07 PM on May 19, 2011

Somewhere, that guy from the old-timey stock footage jumping off a cliff in his wooden bird wings is having a long-awaited chuckle.

Meanwhile, the guys who built the "Octo-plane" that promptly collapsed are thinking "well, we had the right number of wings, just the wrong configuration!"posted by ShutterBun at 10:09 PM on May 19, 2011 [1 favorite]

Wow, that actually makes human-powered flight look less practical than if nobody had ever done it. In what was obviously a very well designed and very light craft, a very athletic person just bared managed to take off, using their entire body at what was obviously a sprinting pace. That really does not bode well for it ever being anything other than a curiosity.

You are familiar with how technological progress works right? You don't start with an optimised product, you start with a proof of concept.

Materials science is advancing rapidly, there's no reason to think they won't be able to continually build lighter and stronger versions of this craft. And I highly doubt that sprinting style is the most efficient energy-transfer mechanism, surely she could get more power from a nice light gearbox. Furthermore they've chosen a quadcopter design which involves a trade-off in reduced efficiency for greater stability, I wouldn't be suprised if they could build a more efficient version of this with, say, 2 rotors on a single axis, or some kind of electronically-assisted stability control. Finally, (and I'm instinctively ducking while I type this) I'm pretty sure an athletic man has a better power-to-weight ratio than an althetic woman.posted by mhjb at 10:19 PM on May 19, 2011 [1 favorite]

Judy Wexler Human is as strong as a horse!, av123

A highly athletic human can output 1 hp initially, but this falls off rapidly so that the average power output over the first minute or so of activity is less than half that. If I remember right, women do have higher strength-to-weight ratios than men, which makes them especially suitable for human-powered aircraft. That's a general statement though, and it might be more difficult to find a female pilot with high enough power output and high enough P/W than a male because there are more male cyclists.

That really does not bode well for it ever being anything other than a curiosity., Mitrovarr

There are no delusions about this. When the Gossamer Condor flew across the english channel, the pilot was near the point of absolute exhaustion and they were surprised he could stand at the end of it. Every other human-powered aircraft has only flown successfully with an extremely physically fit pilot, almost olympian class (the UBC HPH team said they had pilots who vomited after trying out). None of these could be flown by average people. This is a test of human fitness and engineering prowess, not directly intended for practical application (though a lot of the engineering could be applied to micro air vehicles or other very low-speed aircraft).posted by mnemonic at 10:30 PM on May 19, 2011

"You are familiar with how technological progress works right? You don't start with an optimised product, you start with a proof of concept. "

To me, this isn't so much "proof of concept" as it is a case of "proof that with enough scientific advancement, we can demonstrate that the heretofore impossible is...somewhat possible.

No matter how light this device is, it still requires someone to expend enough energy to lift their entire body weight off the ground. Even with 100% efficiency and 0 extra mass, it's a lot to ask, especially for a helicopter type device. Unless / until they come up with some kind of a breakthrough akin to the afterburner or turbo power,(where wasted energy can be harvested and reused) I don't see much future in this.posted by ShutterBun at 10:41 PM on May 19, 2011

True. But it's a cool school project and it (along with similar projects) might result in usable engineering advances: lighter and stronger airframe materials, lighter and stronger engines, and computer stabilization. The stipulation that it be pedal-powered makes engineers work a million times harder to keep things efficient.posted by pracowity at 11:23 PM on May 19, 2011

I guess when human and machine turn into flying cyborg, its not a big deal that everyone is able to figure out you weigh 107 lbs by subtracting gross weight from empty weight.

Could a single person peddling a bike to pump a cylinder full of compressed air, over a course of many days, be able to qualify if that compressed air was able to provide the same (or more) HP than directly driving the system.

I guess it's one definition of human powered. Compensate for the lack of endurance (generating that much energy) by stockpiling it in a compressed gas canisters. I guess it's really a question if the compressed gas could offset the additional load of the engine, their canisters, and the human riding along with it.posted by mrzarquon at 12:23 AM on May 20, 2011

But it's a cool school project and it (along with similar projects) might result in usable engineering advances: lighter and stronger airframe materials, lighter and stronger engines, and computer stabilization.

Oh please! Usable engineering advances do not come from school projects nowdays.

@mrzarquon. You're thinking of a perpetual motion machine.posted by c13 at 12:29 AM on May 20, 2011

No, he's thinking of stored energy. (though I think tortion would be a better storage medium for this kind of thing)posted by ShutterBun at 12:31 AM on May 20, 2011

I was thinking the same thing. Was any compensation made for gear ratios, etc.? Seems like once you overcame the inertia of the propellers, you could slowly work your way up to some pretty fast speeds, via gears.posted by ShutterBun at 12:34 AM on May 20, 2011

No, I was thinking of spending a couple of weeks peddling a bicycle powered air compressor to fill canisters with compressed gas. Then using all that stored energy within a short time period to power a 2HP pneumatic engine (since the engine + canisters weigh more than a person by themselves). The question is if you can store energy efficiently enough that way to offset the additional energy output required to lift the engine.posted by mrzarquon at 12:35 AM on May 20, 2011

Well, I guess I'm not sure what exactly if the compressed gas could offset the additiona means.posted by c13 at 12:35 AM on May 20, 2011

The question is if you can store energy efficiently enough that way to offset the additional energy output required to lift the engine.

There are two questions in this. Efficiency of every energy transformation prosess is always less than 1. So no, human-compressed air engine would not be more efficient than what she's doing right now, asuuming the helicopter stays the same. But since you're suggesting storing energy, of course you can have enough of it to lift the engine.posted by c13 at 12:43 AM on May 20, 2011

The equipment would weigh more because you would need to be able to lift the tanks of compressed air off the ground along with the rest of the equipment. So would there be enough lift generated by a helicopter with a pneumatic engine system powered by compressed air (done by human power, so not nearly the high pressures of traditional compressed gas) to get it off the ground.

I think tortion would be more difficult because you would have to reinforce the frame to be able to support the stresses involved in holding the system under strain. A pneumatic engine could be fitted in place of the pedals on the existing designs.posted by mrzarquon at 12:45 AM on May 20, 2011

Well, I guess I'm not sure what exactly if the compressed gas could offset the additiona means.

He means that all of the apparatus needed to store and release the energy from pedalling would also need to be lifted in flight.

I don't think this fits the definition of 'controlled flight'. I'd think that implies a direct-drive system. It would come down to potential energy vs. kinetic energy. They would have to rule out potential energy systems as one could just walk up a mountain with a hang glider and claim the prize by sitting on an updraft.posted by jimmythefish at 12:45 AM on May 20, 2011

Really, it's just seeing if the rules allow for energy storage of any type. I saw they had mentioned an electric drive system was considered a valid entry, because it drove the electric motors directly off a DC generator that the bicyclist powered (which is kind of an ingenious way to get around the complexities of transferring the power across the delicate frames, each gear adds weight).posted by mrzarquon at 12:49 AM on May 20, 2011

But even gasoline in a tank can only be considered "potential energy" in the the same way human-created compressed air, rubber tension, or whatever would be.

Granted, this is probably not the "according to Sikorsky" definition, but it's still controlled flight.

(then again I suppose you could just throw a corpse on a fire and create a human-powered steam engine, so I dunno)posted by ShutterBun at 12:51 AM on May 20, 2011

But even gasoline in a tank can only be considered "potential energy" in the the same way human-created compressed air, rubber tension, or whatever would be.

Right - extrapolating often exposes the weakness in the argument. In such a context nobody in their right mind would consider a gasoline-powered helicopter 'human-powered' other than the fact that it was made by humans.posted by jimmythefish at 12:55 AM on May 20, 2011

She needs to produce about 0.6 hp just to hover her own weight. If she's not producing that much during the flight, but using some sort of stored energy, she may as well fly a regular helicopter.posted by c13 at 12:59 AM on May 20, 2011

Oh please! Usable engineering advances do not come from school projects nowdays.

No, probably not, not directly -- they aren't going to take a piece of that pedal-powered toy helicopter and put it on a production machine -- but it's an engineering school training engineers to work on hard problems like this. A shitload of current and future aerospace engineers designed and built that machine, and that is where the results will come from in the long run.posted by pracowity at 1:01 AM on May 20, 2011

Oh please! Usable engineering advances do not come from school projects nowdays.

Also, pure research environments with no development pressures or careers at stake can work at doing wacky things like this and spend way more time on them than industry can.posted by jimmythefish at 1:05 AM on May 20, 2011

Really all this experiment shows (once again) is that humans are not birds, they cannot do work fast enough (don't have enough power) to overcome the force of gravity. Regardless of contraptions they come up with. Do you understand this, Pracowity? Human body is not powerful enough for flight. Any mechanical (or other) addition will only reduce the available power since the efficiency of force transmission is always less than one. It is not something you can engineer your way out of.
Making engineering students do this sort of thing is like making physics students design perpetual motion machines -- gets your mind working, but no one expects any breakthroughs.posted by c13 at 1:10 AM on May 20, 2011

I should probably be more specific and say that human body is not powerful enough to hover, rather than fly.posted by c13 at 1:12 AM on May 20, 2011

But it's a pretty good way to demonstrate that pulleys/wings/gears can (with the proper outside forces) achieve mechanical advantage, which is a pretty big deal.posted by ShutterBun at 1:28 AM on May 20, 2011

A stick and a rock can demonstrate the principle of mechanical advantage too.posted by c13 at 1:40 AM on May 20, 2011

True, but we're not talking about the viewpoints of "people who were rejected from the Mr. Wizard auditions in the first round."posted by ShutterBun at 2:04 AM on May 20, 2011 [1 favorite]

Hmm...I wonder....what if you gave the pilot a little bottle of air and flooded the gymnasium with sulfur hexafluoride? It's inorganic, colorless, odorless, non-toxic and non-flammable but also roughly 5 times as dense as air. Do the Sikorsky prize rules say anything about the medium in which the flight has to occur?

Also, what do the rules say about doping the pilot to the gills on performance enhancing drugs?posted by jedicus at 5:13 AM on May 20, 2011

With meat having a couple hundred K Cal per 3oz serving, and gasoline having 31,000 K Cal a gallon, then if Judy was combusted efficiently, she'd be good for about 2 gallons of gas.posted by StickyCarpet at 5:23 AM on May 20, 2011 [2 favorites]

If those puny scientists were really interested in improving the power of the pilot, they would have exposed her to the blast of a Gamma Ray Bomb first.posted by digsrus at 5:37 AM on May 20, 2011

Seems like once you overcame the inertia of the propellers, you could slowly work your way up to some pretty fast speeds, via gears.

I don't think so. The rotors will act as natural speed governors, with a pretty low speed limit, I'm guessing. And the resistance encountered by the rotors will increase with the square of their speed, so pedaling would get very hard very fast.

I'd also guess that with all the engineering that obviously went into this, they optimized the gearing to produce a desired RPM at the rotors at a power-efficient RPM at the pedals.posted by adamrice at 6:16 AM on May 20, 2011

I'm not sure why they thought it was a good idea to put a small athlete in there. Imagine that power-to-weight ratio for the pilot is a constant, regardless of pilot weight. As the pilot gets heavier, the total weight will tend towards the pilot's weight, and the power-to-weight ratio of the whole kit will tend towards the theoretical maximum of the pilot alone.

e.g. in this attempt, you have a ratio of 750W/94kg = 8W/kg. If you double the pilot weight and double the pilot peak power, you get 1.5kW/142kg = 10.5 W/kg. If you stick Chris Hoy in there, you have 2.5kW/139kg = 18W/kg.posted by Jakey at 7:55 AM on May 20, 2011

I can beat that both in hight and relative energy used; I have this magical technology called "jumping".

But seriously, that was a very neat intellectual exercise made real, and she seriously put forth an effort to get those three or so inches off the ground. I don't see human power being the future of flight, but with a rig like that and a very small electric motor and battery, you might be able to actually do a neat new form of ultralight.posted by quin at 8:50 AM on May 20, 2011

I wish they would have interviewed her. The high fiving was cool though.posted by cashman at 8:59 AM on May 20, 2011

Imagine that power-to-weight ratio for the pilot is a constant, regardless of pilot weight.

This is a bad assumption. The Square-Qube Law is applicable here. Smaller humans will, all else being equal have better power to weight ratio. I speculate that they got the smallest adult athlete out of the eligible candidates for this reason.posted by Catfry at 11:26 AM on May 20, 2011

There was also an article in the Washington Post last week about this. The Sikorski prize apparently requires three meters altitude and a 60 second hover, which the U-Md. team seems pretty far from reaching. (But with the 42-foot rotors, three meters should have them remaining in ground effect.)posted by exogenous at 12:33 PM on May 20, 2011

So, how is it that a human-powered airplane could fly across the English channel, but a human-powered helicopter could get only a few inches off the ground for a short period? Was the plane, for practical purposes, just a steerable kite?posted by beagle at 6:30 PM on May 20, 2011

Airplanes are more efficient users of power than helicopters, as far as being able to accelerate to take off and in requirements to maintain level flight.

Another way to think about it: plenty of engine-less airplanes (gliders) are built and used routinely to stay aloft for hours using natural sources of lift such as thermals. I don't think there are any gliders effective based on a helicopter-type design.posted by exogenous at 6:00 AM on May 21, 2011

GUYS GUYS GUYS THEY NAMED A HELICOPTER AFTER ME!!1!......guys?posted by gamera at 6:28 PM on May 22, 2011 [1 favorite]

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